I am trying to attach an external monitor to my MacBook Pro using VGA to DVI adapter and then DVI to Thunderbolt.
I have MacBook Pro 2012 with Retina display and the monitor is Acer V223HQV.
Problem is that when I connect it the external monitor doesn't start working but is visible under System Preferences → Displays. Anyone can help me out here? What extra information I can give you to help solve this problem?